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New Member

VPN Client 3.5.2 on Windows XP, got Error 720 on Dialup Connection

I searched the Internet, but did not find anything regarding this topic. I have setup the PIX firewall for VPN Clients, Windows 98 Users do not have any problems connecting to the PIX. However, when I tried to install VPN client on a Windows XP pc, the dialup connection to the ISP did not work. got error 720, related to PPP negotiation. As long as I remove Cisco VPN Client, the Dialup works again.

By the way, before I tried to install VPN client today, the user tried to install the old version of VPN client which did not support XP. I uninstalled it through Control Panel. Does VPN client change some registries in the XP and corrupt the PPP? I verified the Dialup settings, TCP/IP was enabled, PPP allow any authentication, everything seems normal.

I would appricate if any one could give me some clue.


New Member

Re: VPN Client 3.5.2 on Windows XP, got Error 720 on Dialup Conn

One thing comes to mind… AOL. If your SP is AOL (or Compuserve), try uninstalling their software, installing the Cisco client, then re-installing AOL. Since AOL’s TCP stack rides on the Windows stack, that might be causing a conflict. In any case, you should call Cisco about it. You might have a unique situation and have found a bug.